Successfully complete the game to unlock the following options.
Bloody Footprints (always leave bloody footprints)
Extra Blood (creatures more bloodied when attacked)
Noise Filter (sharpens the graphics)
Torch Projection (project image of smiley face, soccer ball, jack-o-lantern or the mark of Samuel from flashlight)
Walk/Run (toggles running or when Square is held)
Codebreaker suit
Press Up(2), Down(2), Left, Right, Left, Right, X, Circle at any time during your second or later replay.
Endings
Complete the indicated task to unlock the corresponding ending.
Ending
How to unlock
Bad
Kill 200 enemies during your second playthrough.
Good
Complete the game.
UFO
Use Room 502 Key at the motel room.
Fists
Conserve your melee weapons and use your fists. Technically your fists are your fastest weapon (and the strength of them never goes down).
Health and energy drinks
After you exit from the back door of the hospital, wander around a little bit to discover the health and energy drinks as well as other disposable weapons: a vase, 2x4, and a spike over by the bakery.
Invisible enemies
In the place where Lisa tells you to go, you will eventually encounter a room with a circular object in the middle with three doors on the left, top, and right side of it. In this room, you might see invisible enemies wearing a mask of some sort. Look for the mask. It will always shine when you move your flashlight around.
Rewards
Complete the indicated task to unlock the corresponding reward.
Reward
How to unlock
Ambassador Accolades (Tesla Rifle, Space Outfit costume, and UFO Ending)
Pick up "Key to Room 502" on the stairs at the beginning of the game and use it in the motel. You must have completed the game once before to unlock this.
Brawler costume
Kill over 50% of enemies with only your fists.
Butcher Accolade (Great Cleaver weapon, Butcher costume that grants immunity from Straightjacket acid spit, and Bad Ending)
After completed the game once, replay it and accumulate 100 kills. At the end of the game (not the UFO Ending) you will see what Travis has become.
Cartographer costume
Check the map less then 25 times.
Collector costume
Collect more then 300 items.
Daredevil
Complete the game without using any saved games.
Explorer costume
Run or walk over 22.5 km.
Fireman Accolade (Fireman's Axe weapon and Fireman Costume)
Rescue Alessa from the fire at the start of the game in under 80 seconds.
Savior Accolade (Lonely Moon gauntlets weapon, Lonely Moon Leather costume, and Good Ending)
Complete the game. The Good Ending is the default ending unless you qualify for the UFO or Bad Ending.
Savior costume
Complete the game.
Sharpshooter costume
Kill over 75% of enemies with a firearm.
Sprinter Accolade (Fitness Costume that grants Unlimited Fatigue)
Complete the game in under two hours.
Stalker Accolade (Night Vision Goggles and Black Ops costume)
Have the flashlight on less than three hours during the game.
Weaponsmith costume
Kill over 75% of enemies with melee weapons.
Tesla Rifle
How to unlock Tesla Rifle: Beat game once & save. Reload game save & find room key 502. It is north of the hospital, up the long flight of stair's at the top of them. Play thru the game until you are at the Motel level. Use it to open the door & you will get the UFO ending. Save your game & reload it & the Tesla Rifle will be in your inventory.
Bonus options...